Thickened fabric conditioners

ABSTRACT

The present invention relates to thickened fabric conditioners, which fabric conditioners contain a particular polymeric thickener, which is obtained by polymerizing from 5 to 100 mole percent of a cationic vinyl addition monomer, from 0 to 95 mole percent of acrylamide, and from 70 to 300 ppm of a difunctional vinyl addition monomer cross-linking agent. As compared to such compositions comprising a similar product but obtained from a polymerization reaction using between 5 and 45 ppm cross-linking agent considerable advantages are obtained. Especially, the delivery of fragrance present in the softening composition is more efficiently carried over to the fabrics to be treated.

[0001] This application is a continuation-in-part of prior co-pendingU.S. application Ser. No. 10/006,337 filed Dec. 3, 2001 which in turn isa continuation-in-part of U.S. application Ser. No. 09/749,183 filedDec. 27, 2000, the disclosures of which are incorporated herein.

TECHNICAL FIELD OF THE INVENTION

[0002] The present invention relates to fabric conditioningformulations, and especially to rinse-cycle fabric conditioners,comprising at least one fabric softener, and at least one thickeningagent for water-based compositions. More specifically, these fabricconditioning formulations also contain at least one fragrance.

BACKGROUND OF THE INVENTION

[0003] Conventionally, most domestic liquid detergents and liquid fabricconditioning or fabric softener compositions make use of thickeningproperties of surfactant ingredients or added salts to come to a desiredrheology. The last decade, however, there is a growing need to come toformulations that are physically and Theologically stable at ambientconditions for at least a month or so. Such formulations generallycontain specific thickeners in amounts leading to the desiredviscosities and giving suitable stabilities.

[0004] WO 90/12862 (BP Chemicals Ltd.) discloses aqueous based fabricconditioning formulations comprising a water dispersible cationicsoftener and as a thickener a cross-linked cationic polymer that isderivable from a water soluble cationic ethylenically unsaturatedmonomer or blend of monomers, which is cross-linked by 5 to 45 ppm of across-linking agent comprising polyethylenic functions. More inparticular, these cationic polymers are formed from monoethylenicallyunsaturated monomer that is either a water soluble cationic monomer oris a cationic blend of monomers that may consist of cationic monomersalone or may consist of a mixture of cationic and non-ionic monomers inthe presence of a cross-linking agent. Polymeric thickeners which are inaccordance with this prior art publication are referred to herein in thedescription and Examples for comparative purposes; they are usuallyreferred to as “BP polymer”.

[0005] The preferred amount of cross-linking agent used in thepolymerization is said to be selected in such a way that the IonicRegain reaches a peak or plateau and preferably is between 10 and 25ppm.

[0006] A commercial product covered by said WO 90/12862 is across-linked cationic copolymer of about 20% acrylamide and about 80% oftrimethylammonioethylmethacrylate salt cross-linked with 5-45 ppmmethylene bis acrylamide (MBA). The cross-linked polymer is supplied ina liquid form as an inverse emulsion in mineral oil. It is referred toin the present description as the “BP polymer”.

[0007] In EP-A-0 799 887 liquid fabric softening compositions aredescribed which are said to exhibit an excellent viscosity and phasestability as well as softness performance, which compositions comprise:(a) 0.01-10 wt. % of a fabric softener component, (b) at least 0.001% ofa thickening agent selected from the group of (i) associative polymershaving a hydrophilic backbone and at least two hydrophobic groups permolecule attached to the hydrophilic backbone, (ii) the cross-linkedcationic polymers described in the above-mentioned WO 90/12862,cross-linked by 5-45 ppm of cross-linking agent comprising polyethylenicfunctions and (iii) mixtures of (i) and (ii), and (c) a componentcapable of sequestering metal ions.

[0008] In Research Disclosure page 136, no. 429116 of January 2000, SNFFloerger has described cationic polymeric thickeners that are useful infabric softeners. The thickeners described are branched and/orcross-linked cationic polymers formed from monoethylenically unsaturatedmonomers being either water soluble cationic monomers or blends ofcationic monomers that may consist of cationic monomers alone or maycomprise a mixture from 50-100% cationic monomer or blend thereof andfrom 0-50% of non-ionic monomers in the presence of a cross-linkingagent in an amount of 60 to 3000 ppm and of chain transfer agent in anamount of between 10 and 2000 ppm. The cationic monomers are selectedfrom the group of dimethylaminopropyl methacrylamide,dimethylaminopropylacrylamide, diallylamine, methyldiallylamine,dialkylaminoalkylacrylate and methacrylate, dialkylaminoalkyl acrylamideor methacrylamide, derivatives of the previously mentioned monomers orquaternary or acid salts thereof. Suitable non-ionic monomers areselected from the group consisting of acrylamide, methacrylamide,N-alkyl acrylamide, N-vinyl pyrrolidone, vinylacetate, vinyl alcohol,acrylate esters, allyl alcohol, and derivatives thereof. Thecross-linking agents are methylene bisacrylamide and all diethylenicallyunsaturated compounds.

[0009] U.S. Pat. No. 4,806,345 teaches personal care compositions whichhave as a thickening agent a cross-linked cationic vinyl additionpolymer. The personal care compositions include water, at least onecosmetically-active agent and such a thickening agent that is preferablyderived from the polymerization of a cationic vinyl addition monomer,acrylamide, and 50-500 ppm of a difunctional vinyl addition monomer forcross-linking purposes. Preferred embodiments described in U.S. Pat. No.4,806,345 only differ from the preferred products of WO 90/12862 in thatmore (of the same) cross-linking agent is used in the polymerizationreaction.

OBJECTS OF THE INVENTION

[0010] It is a first object of the present invention to provide fabricconditioning or softener compositions that are more stable than thesoftener compositions described in WO 90/12862 and EP-A-0 799 887.

[0011] It is a second object to develop fabric softener compositionsthat are easier and quicker to prepare.

[0012] It is a third object of the present invention to provide fabricsoftener compositions that are less sensitive to differences in waterhardness, even without the necessity of using a co-softener, so that oneand the same commercial composition could be marketed throughout theentire world.

[0013] It is a further object to come to fabric conditioner compositionsthat provide better fragrance retaining capacities. In laundry productssuch as fabric softeners the perfume additives make laundry compositionsmore aesthetically pleasing to the consumers. Besides the point ofpurchase perception, another objective of the use of perfume additivesis to impart a pleasant and longer lasting fragrance to fabrics that aretreated therewith. However, the amount of perfume carry-over is marginaldue to much of it being lost down the drain during the wash. Oncedeposited on the fabric surface, there is a need for a controlledrelease of the fragrance over a long period of time. So, there is a needto deliver perfume onto fabrics more effectively, so that it can bereleased for a longer period of time.

[0014] Other objectives and advantages of the compositions of thepresent invention will follow from the detailed descriptionherein-below.

SUMMARY OF THE INVENTION

[0015] In accordance with the present invention, there are providedfabric softening compositions which are based on the use of awater-soluble cross-linked cationic vinyl polymer which is cross-linkedby a cross-linking agent comprised of from about 70 to 300 ppm of adifunctional vinyl addition monomer cross-linking agent.

[0016] A first fabric softening composition in accordance with theinvention comprises:

[0017] (a) from 0.01% to 35%, by weight, of a cationic softener;

[0018] (b) at least 0.001%, by weight, of a water soluble cross-linkedcationic polymer derived from the polymerization of from 5 to 100 molepercent of a cationic vinyl addition monomer, from 0 to 95 mole percentof acrylamide, and from 70 to 300 ppm of a difunctional vinyl additionmonomer cross-linking agent; and

[0019] (c) a perfume, wherein the composition does not contain analkoxylated ether of the formula:

[0020] wherein R is selected from the group consisting of H and C₁-C₃₀staight chain or branched chain alkyl, m is an integer from 0 to about6, R′ is selected from the group consisting of methyl and ethyl, and nis an integer from about 3 to about 30; or an alkoxylated diether of theformula:

[0021] wherein R″ is selected from the group consisting of methyl andethyl, p is an integer from about 1 to about 6, and ech q and r areindependently selected so that their sum is an integer from about 3 toabout 30.

[0022] A preferred cationic softener is an esterquat softener having thefollowing structural formula:

[0023] wherein R4 represents an aliphatic hydrocarbon group having from8 to 22 carbon atoms, R₂ and R₃ represent (CH₂)—R₅ where R₅ representsan alkoxy carbonyl group containing from 8 to 22 carbon atoms, benzyl,phenyl, (C1-C4)-alkyl substituted phenyl, OH or H; R1 represents(CH₂)_(t)R₆ where R₆ represents benzyl, phenyl, (C1-C4)-alkylsubstituted phenyl, OH or H; q, s, and t, each independently, representan integer from 1 to 3; and X⁻ is a softener compatible anion.

[0024] The term “perfume” or “fragrance” as used herein refers toodoriferous materials which are able to provide a pleasing fragrance tofabrics, and encompasses conventional materials commonly used indetergent compositions to counteract a malodor in such compositionsand/or provide a pleasing fragrance thereto. The perfumes are preferablyin the liquid state at ambient temperature, although solid perfumes arealso useful. Included among the perfumes contemplated for use herein arematerials such as aldehydes, ketones, esters and the like which areconventionally employed to impart a pleasing fragrance to liquid andgranular deterent compositions. Naturally ocurring plant and animal oilsare also commonly used as components of perfumes. Accordingly, theperfumes useful for the present invention may have relatively simplecompositions or may comprise complex mixtures of natural and syntheticchemical components, all of which are intended to provide a pleasantodor or fragrance when applied to fabrics. The perfumes used indetergent compositions are generally selected to meet normalrequirements of odor, stability, price and commercial availability. Theterm “fragrance” is often used herein to signify a perfume itself,rather than the aroma imparted by such perfume.

[0025] Another fabric softening composition in accordance with theinvention comprises:

[0026] (a) from 0.01% to 35%, by weight, of a cationic softenercomprising a biodegradable fatty ester quaternary ammonium compoundhaving the formula:

[0027] wherein R₁ is C1-C4 alkyl;

[0028] R₂ and R₃ are β-C8-C22-acyloxy ethyl or β-hydroxy ethyl;

[0029] R4 is an aliphatic hydrocarbon group having from 8 to 22 carbonatoms;

[0030] q is an integer from 1 to 3; and

[0031] X⁻ is a softener compatible anion;

[0032] (b) at least 0.001% of a water-soluble cross-linked cationicpolymer derived from the polymerization of from 5 to 100 mole percent ofa cationic vinyl addition monomer, from 0 to 95 mole percent ofacrylamide, and from 70 to 300 ppm of a difunctional vinyl additionmonomer cross-linking agent; and

[0033] (c) at least 0.001% of a chelating compound capable f chelatingmetal ions and selected from the group consisting of amino carboxylicacid compounds, organo aminophosphonic acid compounds and mixturesthereof.

[0034] The present invention is predicated on several discoveriesattendant to the use of the above-described cross-linked cationicpolymer in fabric softening compositions:

[0035] (1) the significantly improved perfume delivery to fabrics whichoccurs when using the above-described fabric softening compositioncontaining the aforementioned cross-linked cationic polymer and aperfume as compared to the use of an identical softening composition butin the absence of said cationic polymer; and

[0036] (2) the signifcantly enhanced stability of a fabric softeningcomposition as described above containing the defined esterquat softenerand the defined cross-linked cationic polymer in the presence of achelating compound as compared to an identical softening compositionwith chelating compound but which contains a cross-linked cationicpolymeric thickener of the prior art which is different from thatclaimed and described herein.

DETAILED DESCRIPTION OF THE INVENTION

[0037] The thickening polymer used in the compositions of the presentinvention is a cross-linked cationic vinyl polymer which is cross-linkedusing a cross-linking agent of a difunctional vinyl addition monomer ata level of from 70 to 300 ppm, preferably from about 75 to 200 ppm, andmost preferably of from about 80 to 150 ppm. These polymers are furtherdescribed in U.S. Pat. No. 4,806,345 and the above-identified ResearchDisclosure, which documents are both incorporated herein underreference.

[0038] Generally, such polymers are prepared as water-in-oil emulsions,wherein the cross-linked polymers are dispersed in mineral oil, whichmay contain surfactants. During finished product making, in contact withthe water phase, the emulsion inverts, allowing the water solublepolymer to swell.

[0039] The most preferred thickener for use in the present invention isa cross-linked copolymer of a quaternary ammonium acrylate ormethacrylate in combination with an acrylamide comonomer.

[0040] When compared with a corresponding thickener (same ratio of thesame comonomers; same cross-linking agent) that is prepared while using5-45 ppm cross-linking agent in the polymerization, the thickenerrequired in the present invention delivers—under similar conditions—afinished product which has a prolonged physical stability (noseparation, limited viscosity change), and which disperses better inwater. More in particular, it was found that the thickener based on 5-45ppm cross-linking agent exhibits instabilities upon long term storagewhile varying process and formula composition, which problems are, atleast partly, overcome while using the amount of cross-linking agentrequired by the present invention. In addition, as compared to thecompositions of the present invention, the compositions containing thecopolymer cross-linked with 5-45 ppm cross-linking agent are found to bemore sensitive to shear and unstable in presence of high level ofelectrolyte.

[0041] The thickener required in accordance with the present inventionprovides fabric softening compositions showing long term stability uponstorage and allows the presence of relatively high levels ofelectrolytes without affecting the composition stability. Besides, thefabric softening compositions remain stable when shear is appliedthereto.

[0042] The chelating compounds of the invention are capable of chelatingmetal ions and are present at a level of at least 0.001%, by weight, ofthe fabric softening composition, preferably from about 0.001% (10 ppm)to 0.5%, and more preferably from about 0.005% to 0.25%, by weight. Thechelating compounds which are acidic in nature may be present either inthe acidic form or as a complex/salt with a suitable counter cation suchas an alkali or alkaline earth metal ion, ammonium or substitutedammonium ion or any mixtures thereof.

[0043] The chelating compounds are selected from among amino carboxylicacid compounds and organo aminophosphonic acid compounds, and mixturesof same. Suitable amino carboxylic acid compounds include:ethylenediamine tetraacetic acid (EDTA); N-hydroxyethylenediaminetriacetic acid; nitrilotriacetic acid (NTA); and diethylenetriaminepentaacetic acid (DEPTA).

[0044] Suitable organo aminophosphonic acid compounds include:ethylenediamine tetrakis(methylenephosphonic acid); 1-hydroxyethane1,1-diphosphonic acid (HEDP); and aminotri(methylenephosphonic acid).

[0045] Softener formulas using the thickener in accordance with thepresent invention are in addition less stringy than similar formulas,wherein the thickener as described in WO 90/12862 is present.

[0046] Furthermore, there are also manufacturing advantages associatedto the thickener obtained in a polymerization reaction using 70-300 ppm,preferably 75-200 ppm, most preferably 80-150 ppm cross-linking agent,which manufacturing advantages encompass that the structure of thesoftener composition builds much faster; the viscosity of the softenerformula of the invention develops immediately after making. In addition,the softening compositions disperse easier in water.

[0047] The use of the thickener obtained in a polymerization reactionusing 70-250 ppm, and preferably 80-150 ppm cross-linking agent,provides a very valuable benefit for manufacturing, as the time requiredfor the polymer to build the structure is much shorter than with thepolymeric thickener based on 5-45 ppm cross-linking agent. Thisrepresents also additional consumer's benefits, as it improves the easeof softener pouring but also the physical energy required to dispersethe finished product in water during hand wash practices.

[0048] More in detail, the polymeric thickeners used in accordance withthe present invention have a faster swelling kinetic in water (3 mininstead of 15 min for polymeric thickeners described in BP's WO90/12862) as well as in aqueous based fabric softening composition (0min after making instead of 30 to 60 min for the BP product) improvingthe manufacturing control of quality for process and products.

[0049] The swelling kinetics are, moreover, independent from the fabricsoftening composition (actives level, emulsifier level) and from theprocess conditions (equipment, shear).

[0050] Furthermore, advantages are obtained in the overall performancesin a fabric softening composition of the present invention versus asimilar composition including the BP polymer. More particular, a higheroverall phase stability upon aging is obtained; there is a lowersensitivity to electrolytes; there is a lower sensitivity to shear; andthere is a higher dispersibility of the finished product in water.

[0051] In a very important aspect of the present invention, it was foundthat the compositions of the present invention significantly improve thefragrance deposition on fabrics, especially under hard water conditions(washing conditions in Europe). In this light, it is noted that thepresent inventors have recently found that under US washing conditions(relatively low water hardness) the polymeric thickener described in WO90/12862 improves fragrance delivery; yet the composition containingthis thickener does not perform well in delivering fragrance underEuropean washing conditions (higher water hardness).

[0052] Preferred Embodiments

[0053] In the compositions of the present invention various types ofsofteners can be used. The softeners can be of the category of cationic,nonionic, and anionic surfactants. In addition, other conventionalingredients for fabric softening and conditioning compositions, such asclays, silicones, fatty alcohols, fatty esters and so on, may bepresent.

[0054] Preferably cationic softeners are present, and especiallypreferred are softeners such as esterquats, imidazolinium quats, difattydiamido ammonium methyl sulfate, and ditallow dimethyl ammoniumchloride. Suitable cationic softeners are described in U.S. Pat. No.5,939,377, U.S. Pat. No. 6,020,304, U.S. Pat. No. 4,830,771, U.S. Pat.No. 5,501,806, and U.S. Pat. No. 4,767,547, all of which areincorporated herein by reference for this reason.

[0055] The most preferred softener for our invention is the one producedby reacting two moles of fatty acid methyl ester with one mole oftriethanolamine followed by quaternization with dimethyl sulfate(further details on this preparation method are disclosed in U.S. Pat.No. 3,915,867). The reaction products are 50% diesterquat (a) material,20% monoester (b) and 30% triester (c):

[0056] In the present specification, the above reaction product mixtureof triethanolamine esterquat is often referred to simply as esterquat.It is commercially available from, e.g., Kao Corp. as Tetranyl AT1-75™.

[0057] In esterquat softener systems, upon dilution in the rinse liquor,there are two types of particles formed, a hydrophobic multi-lamellarvesicle and a more hydrophilic single layer micelle. Both of theseparticles act as carriers for the fragrance or perfume, the vesiclestend to deposit onto the fabric, whereas the micelles tend to stay inthe rinse water and therefore go down the drain. The present inventorshave found that with the addition of a water swellable polymer, such asBP Polymer 7050™, a polymeric thickener within the scope of WO 90/12862,or any other water swellable polymer, a shift in the equilibrium occurscausing there to be more abundant, larger and more stable vesicles, andfewer micelles and free monomer in the rinse liquor, resulting in abetter delivery of fragrance to the fabric surface.

[0058] Cationic polymeric thickeners are water soluble and, if theirmolecular weigh is high enough, they can thicken aqueous compositions.

[0059] How the degree of cross-linking affects the rheologicalproperties of the finished product is a complex question. Withoutwishing to be bound to any theory, the following is noted.

[0060] Without any cross-linking agent, the thickening capacity of thistype of polymer depends on the polymer-water interactions, temperature,concentration and molecular weight.

[0061] For a given molecular weight, the viscosity of an aqueoussolution increases with polymer concentration. At low concentrations,viscosity increases linearly with concentration. In case of favorablepolymer-water interactions, positive deviation from linearity isobserved; it is related to the second virial coefficient. At a givenconcentration referred to as C*, the viscosity jumps to very high valuesand a significant elastic component is observed. This elasticity comesfrom the entanglements of the polymer chains, which start to overlap insolution.

[0062] C* is a function of the molecular weight. The radius of girationof a polymer coil increases with a power of the molecular weight ofbetween 0.5 (in a poor solvent (in theta conditions)) and 0.8 (in a verygood solvent) (Flory's theory). This means that the volume of a polymercoil increases faster than the molecular weight. As a result, theconcentration above which chains overlap (C*) decreases as molecularweight increases.

[0063] The way C* is affected by the cross-linking level is non-linear.The effect of a low cross-linker level is mainly chain extension. Thisis the case if there is up to one cross-linker molecule per polymerchain. In such a case, the effect of increasing the concentration ofcross-linker is the same as increasing the molecular weight, so a highercross-linker amount will result in more effective thickening. However,higher levels will eventually lead to swelling restriction, due to areduction of the mean distance between cross-link nodes.

[0064] The preferred polymeric thickener preferred in accordance withthe present invention has a cross-linker concentration of 80 to 150 ppmin the polymerization reaction. With this value, considerable higherthan for the thickener described in WO 90/12862, a finished product isachieved which is significantly more stable on ageing and more robustthan a similar product prepared with a polymeric thickener within thescope of WO 90/12862, the BP product.

[0065] Another difference is the lower stringiness of product of theinvention as compared to the BP product. A lower stringiness is a greatconsumer advantage because the lower the stringiness, the lower thechance of messy leaks. Stinginess can be assessed by the firstdifference of normal stresses as measured in a steady shear Theologicalexperiment. An aqueous solution comprising the polymeric thickener inaccordance with the present invention has a lower normal stressdifference than the composition containing the BP polymer under the sameconditions. This is in line with the observed lower stringiness of thefinished product. In this light, reference is made to FIG. 1, whereinthe stringiness is plotted versus the shear rate for the BP polymer andthe polymer of the present invention (SNF polymer).

[0066] Another advantage of the polymeric thickener used in accordancewith the present invention is the much higher ionic regain, which isabout 45-60% compared to about 15-30% for the BP polymer. (Ionic regainis measured by comparing the availability of the cationic charges beforeand after the polymer aqueous solution is submitted to high shear.) Highionic regain means more cationic charges which are not easilyaccessible. This characteristic may explain the better resistance toelectrolytes exhibited by SNF polymer.

[0067] From a molecular point of view, lower normal forces and higherionic regain may be explained by the higher degree of ramifications inthe polymeric thickener used in accordance with the present invention.The cationic charges located close to the ramifications have lessdegrees of freedom and are consequently less accessible. Increasedramification may also explain the better physical stability of thefinished product (even with low electrolyte load).

[0068]FIG. 2 illustrates the advantage of perfume or fragrance impactdescribed above and is further described in Example III, comparing threesoftening compositions: the first (control) with no polymer; the secondcontaining a BP polymer, and the third containing the polymericthickener required by the present invention (SNF polymer). As noted inExample III, the perfume impact of a product in accordance with thepresent invention is 26% higher than the same product formulated with BPpolymer.

[0069] During fabric softener making, the dispersions of the polymericthickener required by the present invention disperses more rapidly thanBP's polymeric thickener and, as illustrated in FIG. 3, the structurereaches its equilibrium value much faster. This presents a very valuablebenefit for manufacturing, as the time required for the polymer to buildthe structure is much shorter than with the BP polymer.

[0070] The present invention will now be further elaborated on the basisof the following non-limiting examples. In the examples, percentages arepercentages active by weight, unless otherwise indicated.

EXAMPLE I

[0071] In this example, it is attempted to show the differences betweena polymeric thickener within the scope of WO 90/12862 (BP 7050; the BPpolymer) and a polymeric thickener required by the present invention(SNF DP/EP 2037B ex SNF, France; the SNF polymer). Both polymers arecross-linked cationic copolymers of about 20% acrylamide and about 80%trimethylammonioethylmethacrylate salt; the difference is in the amountof cross-linking agent (MBA).

[0072] Sample Preparation: Both polymers were extracted by vortexing 1gram of polymer in 2 grams of ethyl acetate followed by centrifugation.The pellet was then re-suspended in acetone, vortexed and againcentrifuged. The polymer pellet was then transferred to vial where it iswashed 3 more times with acetone, allowing the polymer to settle anddecanting the acetone off each time. Each polymer was then dried undernitrogen to remove any acetone.

[0073] The polymers were subjected to Differential ScanningChromatography. The graphs obtained are shown in FIGS. 4 (BP polymer)and 5 (SNF polymer).

[0074] The BP Polymer shows endotherms at 124.16° C. (water), and238.41° C. (melt), and an exotherm at 405.93° C. (decomposition). TheY-axis in both graphs show the heat flow (W/g; watts/gram).

[0075] The SNF Polymer shows endotherms at 94.46° C. (water), and240.73° C. (melt), and an exotherm at 404.18° C. (decomposition).

[0076] The only significant difference observed between the two polymersis the onset of the water endotherm. This is an indication that the BPPolymer holds water more tightly than the SNF Polymer, which is showing,less tightly held, or free water.

EXAMPLE II Rate of Dispersion of Extracted Polymers

[0077] This example is carried out to determine if the faster rate ofdispersion for the SNF polymer is due to the presence of theco-surfactant or due to a difference in the polymer from BP.

[0078] Procedure: Each Polymer was suspended in hexane to create equaland uniform particle sizes in a 10% solution. 1 ml of this suspensionwas transferred to a vial containing 10 ml water. Vials were mixed byinverting 3 times and gellation rate was observed.

[0079] Results: The SNF polymer was completely gelled by the end of theinversions. The BP Polymer still showed large lumps of polymer. Thesample was allowed to stand overnight and the gel was obtained bymorning.

[0080] The data show that the SNF polymer disperses more easily than theBP Polymer in the absence of a co-surfactant. This indicates that thereis an inherent difference between the two polymers other than thepresence or type of co-surfactant or oil.

EXAMPLE III

[0081] Three compositions were prepared as described below whichdiffered with respect to the thickening polymer: the first (control)contained no polymer; the second contained P 7050; and the thirdcontained SNF polymer. The formulas are described in the followingtable: Formula: Percent As Active Ester Quat  8.0% Perfume 0.75% Dequest2000⁽¹⁾ 0.10% Lactic/Lactate Buffer 0.063%  CaCl₂ (10% sol) 0.050% Polymer* 0 or 0.15% De-ionized H₂O to 100%

[0082] Analytical Data: Analysis of Fragrance Deposited onto Fabric bySPME (solid phase micro-extraction) GC/MS. The results are shown in FIG.2.

[0083]FIG. 2 demonstrates that at 100 ppm water hardness, the softenercomposition with SNF polymer delivered significantly more fragrance (73%increase) on the fabric surface (dry) as compared to the control havingno polymer.

[0084]FIG. 2 also demonstrates that the presence of SNF polymer resultedin significantly greater perfume delivery to the fabric surface at 100and 500 parts per million of water hardness as compared to the perfumedelivery from the same softening composition but with BP polymer inplace of SNF polymer. The perfume impact when using the SNF polymerbased composition was 26% higher at 500 ppm hardness than thecomposition formulated with BP polymer.

EXAMPLE IV

[0085] In this example the swelling kinetic of BP and SNF polymers iscompared. A cross-linked polymer, when placed in a suitable solvent,imbibes the solvent and undergoes swelling to an extent determined bythe nature of the polymer and the solvent. By swelling is intended theability of the polymer to thicken the solvent whether it is water or afabric softening composition.

[0086] De-ionized (DI) water was thickened with 0.5% (% of actives inemulsion) of BP 7050 or SNF polymer. The polymer under emulsion form wasrapidly added to DI water through a syringe. The mixing speed was fixedat 250 rpm and dispersion time at 3 minutes. Swelling kinetic was thenfollowed using a Brookfield RVT viscometer (10 rpm, spindle 2). Theresults are shown in FIG. 6.

[0087] As shown in FIG. 6, the final viscosity (24H) of DI waterthickened with SNF polymer is obtained right after making whereas withBP 15 minutes are necessary.

EXAMPLE V

[0088] In this example the effect of the cross-linker level is shown.

[0089] The influence of the cross-linker level on the swelling kineticof a 0.5% SNF dispersion in water was determined. To this end, fourlevels of cross-linker were tested, namely 30, 80, 150 and 200 ppm. Theresults are shown in FIG. 7. It is clear that the higher thecross-linker level is, the higher the viscosity of the resulting gel is.The viscosity increase versus the cross-linker level is however notlinear. The swelling kinetic is independent from the cross-linker level.

EXAMPLE VI

[0090] This example shows the swelling kinetics in fabric softeningcompositions.

[0091] The swelling kinetic of SNF and BP polymers added to RegularFabric softeners was studied using the European formula 5EQ as model:European formula (% nominal) Esterquat:  3.3% Fatty alcohol 0.825%Perfume: Douscent  0.32% Synperonic SA20:  0.2% Thickener 0.115%Dequest:  0.1% Dye: 0.004% KKM/lactic lactate 0.1225%  DI Water balance

[0092] Process: 20 L batch, four flat blade turbine, mixing at 500 rpmone part of water (60° C.), Perfume in AI, thickener at the end (30°C.), 15 min mixing. The results are depicted in FIG. 8.

[0093] As can be seen from this FIG. 8, the final viscosity is obtainedright affter making for the rinse-cycle fabric softener thickened withthe SNF polymer whereas wit the BP polymer 1 to 2 hours are needed. Thethickening efficacy of the SNF polymer appears to be optimal in therange of 80-150 ppm cross-linker. The viscosity decreases outside thisrange.

EXAMPLE VII

[0094] The previous example is repeated, but now using continuous andbatch pilot scale equipment. In the batch process the swelling kineticof SNF and BP polymers has been checked in 5 formulas of reference: (%nominal) FORMULA A Esterquat −90%: 3.3 Fatty alcohol C16-C18 0.825Perfume: Douscent 653 NMR 0.32 Synperonic C13-15 fatty alcohol EO 20:10.2 Thickener 0.115 Dequest 0.1 Dye Royal blue 0.004 KKM 446 0.06 lacticlactate buffer solution 0.0625 Demineralized Water balance to 100FORMULA B Esterquat −90%: 4 Fatty alcohol C16-C18 0.6 Perfume: Douscent653 NMR 0.32 Synperonic C13-15 fatty alcohol EO 20:1 0.2 Thickener 0.125Dequest 0.1 Dye Royal blue 0.004 KKM 446 0.06 lactic lactate buffersolution 0.0625 Demineralized Water balance to 100 FORMULA C Esterquat−90%: 4.5 Perfume: Douscent 653 NMR 0.32 Synperonic C13-15 fatty alcoholEO 20:1 0.2 Thickener 0.175 Dequest 0.1 Dye Royal blue 0.004 KKM 4460.06 lactic lactate buffer solution 0.0625 Demineralized Water balanceto 100 FORMULA D Esterquat −90%: 7.8 Perfume: Douscent 653 NMR 0.32Synperonic C13-15 fatty alcohol EO 20:1 0.2 Thickener 0.15 Dequest 0.1Dye Royal blue 0.004 KKM 446 0.06 lactic lactate buffer solution 0.0625Demineralized Water balance to 100 FORMULA E Esterquat −90%: 3.6Perfume: Larian M 0.2 Synperonic C13-15 fatty alcohol EO 20:1 0.1Thickener 0.14 Dequest 0.1 Dye Royal blue 0.004 KKM 446 0.06 lacticlactate buffer solution 0.0625 Demineralized Water balance to 100

[0095] The results for the FORMULAE A-E are depicted in FIGS. 9a-9 e,respectively. Whatever the formula composition, i.e. the actives level(esterquat and fatty alcohol), the swelling kinetic of the SNF polymeris faster than for the BP polymer. Final viscosity is reached rightafter making for SNF whereas for BP a delay is required.

EXAMPLE VIII

[0096] FORMULA A was used in this example. The mixing devices andemulsifier level have been varied as follows:

[0097] VIIIa: high shear (mixing valve+centrifugal pump), 0.2% of SA20emulsifier

[0098] VIIIb: low shear (mixing valve), 0.2% of SA20 emulsifier

[0099] VIIIc: low shear (mixing valve), 0.3% of SA20 emulsifier

[0100] The results are shown in FIGS. 10a-c. Just like in the batchprocesses, the swelling kinetic of the product of the invention isconsiderably quicker than for the product based on the BP thickener. Nodelay is necessary to obtain the final viscosity with SNF, whereas withthe BP polymer 30 minutes up to 1 hour are needed. Moreover, the SNFswelling kinetics seem independent from the shear level and theemulsifier level.

EXAMPLE IX

[0101] Formula A was tested on the stability. The formula with the BPpolymer exhibits distinct marks of instabilities after 6 weeks of aging,whereas the SNF polymer formula has an almost perfect stability at allaging temperatures: 4° C., RT, 35° C. and 43° C. By distinct marks ofinstabilities are meant: an apparition of a dark ring; and possiblecurdled aspect or evidence of starting flocculation phenomena. See inthis respect FIG. 11.

EXAMPLE X

[0102] In this example the stability to electrolytes is studied. In somefabric softening formulations, salt addition is needed to adjust thefinal viscosity of the finished product. Thus, from a manufacturingpoint of view, the sensitivity of Rinse Cycle Fabric Softeners toelectrolytes is of great interest. In this light, it has been shown thatfabric softening compositions with SNF polymers are significantly lesssensitive to electrolytes than those with BP polymer. This has beenillustrated on the basis of Formula D with 0.01 to 0.03 wt. % of CaCl₂.The electrolyte was post-added to the finished product.

[0103] After six weeks of aging the SNF thickened composition has a verygood stability, whereas in the composition containing the BP polymerhigh instabilities are observed. The instabilities are characterized bythe presence of multi rings and thin curdles at RT, 35° C. and 4° C. At43° C. phase separation occurs.

EXAMPLE XI

[0104] In the present example the stability toward shear is tested. Theformulas with SNF polymer are less sensitive to shear than those with BPpolymer.

[0105] Sensitivity to shear of fabric softeners thickened with SNF andBP polymers was studied using formula A. Formulas were preparedfollowing a batch process at pilot scale. SNF and BP polymers were addedat 0.23% (w %).

[0106] After making, the formulas were submitted to high shear using acentrifugal pump (3 bars). Stability was then compared upon aging.

[0107] After 12 weeks of aging the BP containing composition exhibitsinstabilities as ring and curdled aspect at all aging temperatures;whereas the SNF containing compositions are perfectly stable whateverthe temperature.

1-19. (canceled).
 20. A fabric softening composition comprising: (a)from 0.01% to 35%, by weight, of a cationic softener wherein saidcationic softener is an esterquat which is a biodegradable fatty esterquaternary ammonium compound having the formula:

 wherein R4 represents an aliphatic hydrocarbon group having from 8 to22 carbon atoms, R₂ and R₃ represent (CH₂)_(n)—R₅ where R₅ represents analkoxy carbonyl group containing from 8 to 22 carbon atoms, benzyl,phenyl, (C1-C4)-alkyl substituted phenyl, OH or H; R1 represents(CH₂)_(t)R₆ where R₆ represents benzyl, phenyl, (C1-C4)-alkylsubstituted phenyl, OH or H; q, s, and t, each independently, representan integer from 1 to 3; and X⁻ is a softener compatible anion; (b) atleast 0.001%, by weight, of a water soluble cross-linked cationicpolymer derived from the polymerization of from 5 to 100 mole percent ofa cationic vinyl addition monomer, from 0 to 95 mole percent ofacrylamide, and from 70 to 300 ppm of a difunctional vinyl additionmonomer cross-linking agent; and (c) a perfume.
 21. The fabric softeningcomposition of claim 20, wherein said cationic polymer is derived fromsaid polymerization using 75 to 200 ppm of said cross-linking agent. 22.The fabric softening composition of claim 21, wherein said cationicpolymer is derived from said polymerization using 80 to 150 ppm of saidcross-linking agent.
 23. The fabric softening composition of claim 20,wherein said cationic polymer is a cross-linked cationic vinyl polymer.24. The fabric softening composition of claim 23, wherein said polymercomprises a quaternary ammonium salt of an acrylate or methacrylate. 25.The fabric softening composition of claim 24 wherein said polymercomprises a quaternary ammonium salt of dimethyl aminoethylmethacrylate.
 26. The fabric softening composition of claim 20 furtherincluding a chelating compounds selected from the group consisting ofamino carboxylic acid compounds, organo aminophosphonic acid compoundsand mixtures thereof.
 27. The fabric softening composition of claim 25wherein said chelating compound comprises an amino carboxylic acidcompound.
 28. The fabric softening composition of claim 25 wherein saidchelating compound comprises an organo aminophosphonic acid compound.29. The fabric softening composition of claim 20 which further comprisesa perfume.